Flotation machine



Filed May 15,

FEED P/Pf INVE TOR J. fion@ Vd (h4/M4444 ff@ ATTQRNEYS WITNLSS y 1 Patented Apr. 1, 17.930

ALBERT. L. hIEOW'ARI), OF HOLLIS, TERRITORY OF ALASKA yFILO'.I..A'.I.ION MACHINE Application filed May 13, 1927. Serial No. 191,245.

This invention relates to flotation machines. y

It is necessary in all machines of this type to effect an absorption of a gaseous envelop upon a suitable mineral surface in order to produce successful flotation, therefor, in the absence of air or othergaseous medium flotation is a failure.

It has been proposed in various ways to aerate pulp by beating air into the same in which the beater works in the mass of the pulp and in some cases air is forced through the pulp during beating as a precaution to provide for` a ufficient gaseous medium.

An object o the present invention is the provision of a process and machine for producing flotation with a minimum of energy and a maximum of aeration.

A further object of the invention is the provision of method of producing flotation by throwing the pulp in the form of a film or attenuated condition into a gaseous medium for maximum aerating effect.

This invention will be best understood from a consideration of the following detailed description, in view of the accompanying drawings forming a part of the specification; nevertheless it is to be understood that the invention is not confined to the disclosure, being susceptible of such changes'a'nd modiications which shall define no material departure from the salient features of the inven* tion as expressed in the appended claims.

In the drawings Figure 1 is a plan View of one form of which my invention is susceptible.

Figure 2 is a vertical section ytaken along the line 2-2 of Fig. 1.

Referring more particularly to the drawings 10 designates a base or bottom of a cell of the flotation machine. The base is frustoconically shaped and has a fiattened portion 11 at the center. A cylindrical wall 12 is secured to the periphery of the base or the wall and base may be cast integrally. Anannular aprlpn 13 is secured to the upper end of said wa An inverted cup-shaped member 14 has its lower open end 15 disposed in a horizontal plane passing through the member 11. The upper end 16 of the cup shaped member is closed except for an opening 17 which receives a feed pipe 18 located centrally of the circular member 14. The side wall of the cup shaped member has a plurality of'rows of 55 passages 19 arranged at various horizontal levels, for a purpose which will bepresently explained. The lowermost row of passages 19a are located below the member 11 andk normally below the level 20 of the liquidin the 50 cell 21.

A baffle or deflecting apron 22 is secured to the upper end of the cup-shaped member 14, and has its wall inclined to the vertical so that sufficient flaring is provided at the lower or inner end of the baille to perform an aerating chamber 23 which progressively increases from the upper or/outer end thereofto the inner end. The inner end is. normally submerged in the liquid in the cell. It will be further noted that the inner end of the apron is disposed in a horizontal plane which is below the plane passing through the member 11.

The inner end 24 of the feed pipe 18 is conically shaped with the inner reduced p0r- 75 tion registering with an inlet opening 25 of a rotatable head 26. The pipe 18 is connected in any suitable manner with a source of Supply whereby the pulp is fed continuously to the flotation machine. I

f The tailings are withdrawn through a passage 27 at the bottom of the cell and a baiii'e 28 associated with the passage aids in preventing the loss of froth at this point.

The head 26 may be formed of a plurality 85 of radial arms 29 or the same may be in the shape of a disk. In either case a plurality of radial passages 30 are provided in the head and are in communication with the cent-ral opening 25. The outer ends of the passages w are so arranged that they will throw the pulp directly towards the passages 19 and 19a in the wall of the cup-shaped member 14. A shaft 31 located centrally of the feed pipe 18 has its inner end secured to the head. Saidl shaft is driven through any suitable connection by an engine associated with the plant.

While I have shown one cell it will be appreciated that a battery of the cells may be employed and in which the pulp released from the first cell is passed through succeeding cells of the battery.

The operation of my device is as follows 1- The pul to be treated is forced through or fed by t ie pipe 18 to the head 26 which is revolving at a predetermined speed. This pulp is concentrated at the opening 25 by the conical portion 2li of the feed pipe and thence ber.

ALBERT L. HOWARD.

passes to the radial passages 30 in the head.

From these passages wards the openings 19 and 19"L in the side viali of the cup-shaped member 14, passing through said openings and through the space or chamber 23. During the travel of the pulp through the space between the ends of the passages 30 and the points where the pulp strikes the baiie 22, the pulp is thoroughly aerated.

The froth carrying the mineral ioats upon the surface of the pulp and overflows the apron 13 when the materials which are treated in the cell rise sufficiently.

The passages 30 in the head 26 are sufficiently restricted in depth so that as the head is revolved at a rapid rate, the materials will be thrown into a thin sheet of film into the chamber which is formed by the perforated walls 14.

1. A flotation machine comprising a cell, a rotatable head having a plurality of radial passages disposed in the cell above the level of the liquid in the cell, means for supplying l pulp to the head, a cup-shaped m er embracing the head and provided with a plurality of openings adjacent the radial passages in the head for directing the pulp into the cell.

2. A flotation machine comprising a cell, a rotatable head having a plurality of radial passages disposed in the cell above the level of the liquid in the cell, means for supplying pulp to the head, a cup-shaped member embracing the head and provided with a plurality of openings adjacent the radial passages in the head for directing the pulp into the cell, a baffle embracing the cup-shaped member and forming with the cup-shaped member an air chamber through which the pulp is thrown by the rotating head.

3. A iotation machine comprising a cell, a rotatable head having a plurality of radial passages disposed in the cell above the level of the liquid in the cell, means for supplying pulp to the head, a cup-shaped member the pulp is forced to- 

